DRF-EXTRA-FIELDS

Extra Fields for Django Rest Framework

Possible breaking change in v3.1.0: In this version we have changed file class used in Base64FileField from ContentFile to SimpleUploadedFile (you may see the change here).

Usage

Install the package

pip install drf-extra-fields

Note:

• This package renamed as "drf-extra-fields", earlier it was named as django-extra-fields.
• Install version 0.1 for Django Rest Framework 2.*
• Install version 0.3 or greater for Django Rest Framework 3.*

Fields:

Base64ImageField

An image representation for Base64ImageField

Inherited from ImageField

Signature: Base64ImageField()

• It takes a base64 image as a string.
• A base64 image: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7
• Base64ImageField accepts the entire string or just the part after base64, R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7
• It takes the optional parameter represent_in_base64 (False by default), if set to True it will allow for base64-encoded downloads of an ImageField.
• You can inherit the Base64ImageField class and set allowed extensions (ALLOWED_TYPES list), or customize the validation messages (INVALID_FILE_MESSAGE, INVALID_TYPE_MESSAGE)

Example:

# serializer

from drf_extra_fields.fields import Base64ImageField

class UploadedBase64ImageSerializer(serializers.Serializer):
    file = Base64ImageField(required=False)
    created = serializers.DateTimeField()

# use the serializer
file = 'R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw=='
serializer = UploadedBase64ImageSerializer(data={'created': now, 'file': file})

Base64FileField

A file representation for Base64FileField

Inherited from FileField

Signature: Base64FileField()

• It takes a base64 file as a string.
• Other options like for Base64ImageField
• You have to provide your own full implementation of this class. You have to implement file validation in get_file_extension method and set ALLOWED_TYPES list.

Example:

class PDFBase64File(Base64FileField):
    ALLOWED_TYPES = ['pdf']

    def get_file_extension(self, filename, decoded_file):
        try:
            PyPDF2.PdfFileReader(io.BytesIO(decoded_file))
        except PyPDF2.utils.PdfReadError as e:
            logger.warning(e)
        else:
            return 'pdf'

PointField

Point field for GeoDjango

Signature: PointField()

• It takes a dictionary contains latitude and longitude keys like below

  { "latitude": 49.8782482189424, "longitude": 24.452545489 }

• It takes the optional parameter str_points (False by default), if set to True it serializes the longitude/latitude values as strings

• It takes the optional parameter srid (None by default), if set the Point created object will have its srid attribute set to the same value.

Example:

# serializer

from drf_extra_fields.geo_fields import PointField

class PointFieldSerializer(serializers.Serializer):
    point = PointField(required=False)
    created = serializers.DateTimeField()

# use the serializer
point = {
    "latitude": 49.8782482189424,
    "longitude": 24.452545489
    }
serializer = PointFieldSerializer(data={'created': now, 'point': point})

PolygonField

Polygon field for GeoDjango

Signature: PolygonField()

• It takes a list of orderly pair arrays, representing points which all together are supposed to make a polygon. example:

  A polygon without inner ring represented in 2d array format

  [ [51.778564453125, 35.59925232772949], [50.1470947265625, 34.80929324176267], [52.6080322265625, 34.492975402501536],[51.778564453125, 35.59925232772949] ]

  The same polygon represented in 3d array format

  [ [ [51.778564453125, 35.59925232772949], [50.1470947265625, 34.80929324176267], [52.6080322265625, 34.492975402501536],[51.778564453125, 35.59925232772949] ] ]

  A polygon with inner ring (first element representing exterior and the second one interior ring)

  [ [ [ 0 , 0 ] , [ 3 , 6 ] , [ 6 , 1 ] , [ 0 , 0 ] ], [ [ 2 , 2 ] , [ 3 , 3 ] , [ 4 , 2 ] , [ 2 , 2 ] ]
  ]

Example:

# serializer

from drf_extra_fields.geo_fields import PolygonField

class PolygonFieldSerializer(serializers.Serializer):
    polygon = PolygonField(required=False)
    created = serializers.DateTimeField()

# use the serializer
polygon = [
        [
            51.778564453125,
            35.59925232772949
        ],
        [
            50.1470947265625,
            34.80929324176267
        ],
        [
            52.6080322265625,
            34.492975402501536
        ],
        [
            51.778564453125,
            35.59925232772949
        ]
    ]
serializer = PolygonFieldSerializer(data={'created': now, 'polygon': polygon})

RangeField

The Range Fields map to Django's PostgreSQL specific Range Fields.

Each accepts an optional parameter child_attrs, which allows passing parameters to the child field.

For example, calling IntegerRangeField(child_attrs={"allow_null": True}) allows deserializing data with a null value for lower and/or upper:

from rest_framework import serializers
from drf_extra_fields.fields import IntegerRangeField


class RangeSerializer(serializers.Serializer):
    ranges = IntegerRangeField(child_attrs={"allow_null": True})


serializer = RangeSerializer(data={'ranges': {'lower': 0, 'upper': None}})

IntegerRangeField

from rest_framework import serializers
from drf_extra_fields.fields import IntegerRangeField


class RangeSerializer(serializers.Serializer):
    ranges = IntegerRangeField()


serializer = RangeSerializer(data={'ranges': {'lower': 0, 'upper': 1}})

FloatRangeField

from rest_framework import serializers
from drf_extra_fields.fields import FloatRangeField


class RangeSerializer(serializers.Serializer):
    ranges = FloatRangeField()


serializer = RangeSerializer(data={'ranges': {'lower': 0., 'upper': 1.}})

DecimalRangeField

from rest_framework import serializers
from drf_extra_fields.fields import DecimalRangeField


class RangeSerializer(serializers.Serializer):
    ranges = DecimalRangeField()


serializer = RangeSerializer(data={'ranges': {'lower': 0., 'upper': 1.}}, )

DateRangeField

import datetime

from rest_framework import serializers
from drf_extra_fields.fields import DateRangeField


class RangeSerializer(serializers.Serializer):
    ranges = DateRangeField()


serializer = RangeSerializer(data={'ranges': {'lower': datetime.date(2015, 1, 1), 'upper': datetime.date(2015, 2, 1)}})

DateTimeRangeField

import datetime

from rest_framework import serializers
from drf_extra_fields.fields import DateTimeRangeField


class RangeSerializer(serializers.Serializer):
    ranges = DateTimeRangeField()


serializer = RangeSerializer(data={'ranges': {'lower': datetime.datetime(2015, 1, 1, 0), 'upper': datetime.datetime(2015, 2, 1, 0)}})

PresentablePrimaryKeyRelatedField

Represents related object with a serializer.

presentation_serializer could also be a string that represents a dotted path of a serializer, this is useful when you want to represent a related field with the same serializer.

from drf_extra_fields.relations import PresentablePrimaryKeyRelatedField

class UserSerializer(serializers.ModelSerializer):
    class Meta:
        model = User
        fields = (
            'id',
            "username",
        )

class PostSerializer(serializers.ModelSerializer):
    user = PresentablePrimaryKeyRelatedField(
        queryset=User.objects.all(),
        presentation_serializer=UserSerializer,
        presentation_serializer_kwargs={
            'example': [
                'of',
                'passing',
                'kwargs',
                'to',
                'serializer',
            ]
        },
        read_source=None
    )
    class Meta:
        model = Post
        fields = (
            "id",
            "title",
            "user",
        )

Serializer data:

{
    "user": 1,
    "title": "test"
}

Serialized data with PrimaryKeyRelatedField:

{
    "id":1,
    "user": 1,
    "title": "test"
}

Serialized data with PresentablePrimaryKeyRelatedField:

{
    "id":1,
    "user": {
        "id": 1,
        "username": "test"
    },
    "title": "test"
}

PresentableSlugRelatedField

Represents related object retrieved using slug with a serializer.

from drf_extra_fields.relations import PresentableSlugRelatedField

class CategorySerializer(serializers.ModelSerializer):
    class Meta:
        model = Category
        fields = (
            "id",
            "slug",
            "name"
        )

class ProductSerializer(serializers.ModelSerializer):
    category = PresentableSlugRelatedField(
        slug_field="slug",
        queryset=Category.objects.all(),
        presentation_serializer=CategorySerializer,
        presentation_serializer_kwargs={
            'example': [
                'of',
                'passing',
                'kwargs',
                'to',
                'serializer',
            ]
        },
        read_source=None
    )
    class Meta:
        model = Product
        fields = (
            "id",
            "name",
            "category",
        )

Serializer data:

{
    "category": "vegetables",
    "name": "Tomato"
}

Serialized data with SlugRelatedField:

{
    "id": 1,
    "name": "Tomato",
    "category": "vegetables"
}

Serialized data with PresentableSlugRelatedField:

{
    "id": 1,
    "name": "Tomato",
    "category": {
        "id": 1,
        "slug": "vegetables",
        "name": "Vegetables"
    }
}

read_source parameter

This parameter allows you to use different source for read operations and doesn't change field name for write operations. This is only used while representing the data.

HybridImageField

A django-rest-framework field for handling image-uploads through raw post data, with a fallback to multipart form data.

It first tries Base64ImageField. if it fails then tries ImageField.

from rest_framework import serializers
from drf_extra_fields.fields import HybridImageField


class HybridImageSerializer(serializers.Serializer):
    image = HybridImageField()

drf-yasg fix for BASE64 Fields:

The drf-yasg project seems to generate wrong documentation on Base64ImageField or Base64FileField. It marks those fields as readonly. Here is the workaround code for correct the generated document. (More detail on issue #66)

class PDFBase64FileField(Base64FileField):
    ALLOWED_TYPES = ['pdf']

    class Meta:
        swagger_schema_fields = {
            'type': 'string',
            'title': 'File Content',
            'description': 'Content of the file base64 encoded',
            'read_only': False  # <-- FIX
        }

    def get_file_extension(self, filename, decoded_file):
        try:
            PyPDF2.PdfFileReader(io.BytesIO(decoded_file))
        except PyPDF2.utils.PdfReadError as e:
            logger.warning(e)
        else:
            return 'pdf'

LowercaseEmailField

An enhancement over django-rest-framework's EmailField to allow case-insensitive serialization and deserialization of e-mail addresses.

from rest_framework import serializers
from drf_extra_fields.fields import LowercaseEmailField


class EmailSerializer(serializers.Serializer):
    email = LowercaseEmailField()

CONTRIBUTION

TESTS

• Make sure that you add the test for contributed field to test/test_fields.py and run with command before sending a pull request:

$ pip install tox  # if not already installed
$ tox

Or, if you prefer using Docker (recommended):

docker build -t drf_extra_fields .
docker run -v $(pwd):/app -it drf_extra_fields /bin/bash
tox

README

• Make sure that you add the documentation for the field added to README.md

LICENSE

Copyright DRF EXTRA FIELDS HIPO

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.